IGENITY Tenderness:

Igenity profile Tenderness is a DNA genetic marker panel test comprised of three markers (UoGCAST1, Calpain 4751 and Calpain 316). An increase in “tenderness” is associated with substituting a “C” allele at calpastatin (UoGCAST1) and a “C” allele at both μ-calpain loci (Calpain 4751 and Calpain 316). The following table shows the decrease in “toughness” (Warner-Bratzler Shear Force, lb) for each of the possible genotypes contrasted to the least tender genotype (i.e. UoG-Cast1 “GG”, Capn4751 “TT”, Capn316 “GG”) calculated from a combined analysis of 1209 cattle from four sample populations (Brangus, Charolais x Angus cross, Red Angus and Brahman) used in the validation study.

Genotype

Estimate (lbs.)

Standard Error

Number Obs.

%

UoG-Cast1

Calpain 316

Calpain 4751

CC

CC

CC

-2.3

0.4

18

1.5

CT

-1.1

0.6

8

0.7

TT

0.1

1.0

0

0.0

CG

CC

-1.9

0.3

60

5.0

CT

-1.5

0.3

123

10.2

TT

-0.4

0.5

9

0.7

GG

CC

-1.6

0.3

60

2.7

CT

-1.2

0.3

181

15.0

TT

-0.8

0.2

212

17.5

CG

CC

CC

-1.9

0.3

9

0.7

CT

-0.7

0.5

1

0.1

TT

0.5

1.0

0

0.0

CG

CC

-1.5

0.2

42

3.5

CT

-1.1

0.2

74

6.1

TT

0.1

0.5

4

0.3

GG

CC

-1.2

0.3

23

1.9

CT

-0.8

0.2

91

7.5

TT

-0.4

0.1

204

16.9

GG

CC

CC

-1.4

0.3

2

0.2

CT

-0.2

0.5

1

0.1

TT

1.0

1.0

0

0.0

CG

CC

-1.1

0.2

7

0.6

CT

-0.7

0.1

9

0.7

TT

0.5

0.5

0

0.0

GG

CC

-0.8

0.3

5

0.4

CT

-0.4

0.1

30

2.5

TT

0

63

5.2

The yellow shaded genotypes involve the rare "T-C" haplotype. The low number of animals with this genotype in the data set made it difficult to accurately estimate the size of its effect.

The Calpastatin marker (UogCAST1) and the Calpain haplotypes based on CAPN4751 and CAPN316) were each highly significant. The combination of all three even more so. Each calpastatin “C” was associated with a decrease of 0.4 lb of Warner-Bratzler Shear Force, and substituting the Calpain 4751 “C” - 316 “C” haplotype for the Calpain 4751 “T” - 316 “G” was associated with a decrease of 0.7 lb of Warner-Bratzler Shear Force. Among genotypes with sufficient information there was a 2.3 lb. difference in WBSF between the best (homozygous C at all three markers) and the worst GG-TT-GG (UoGCAST1-CAPN4751-CAPN316). Breeders should not expect gains this large because no herd will consist 100% of the ‘least tender’ genotype.

Test Claims:

Igenity profile Tenderness is a DNA genetic marker panel test offered by Igenity. Increase in “tenderness” is associated with favorable alleles of a marker panel that includes Calpain 4751 (i.e. a “C” allele at the 4751 SNP of calpain ), Calpain 316 (i.e. a “C” allele at the 316 SNP of calpain ), and UofG-CAST1 (i.e. a “C” allele at the UofGCAST1).